Engine connecting rod and crankshaft assembly

Abstract

A four cycle piston engine has a crankshaft that includes a crank pin and a guide pin rotatable as a unit around the crankshaft rotational axis. The connecting rod has a linear trackway that slidably engages the guide pin so that the rod has linear slidable motion relative to the crankshaft. During the power stroke the connecting rod applies a pulling force to the crank pin via a special force-transmitting linkage.

1. A four cycle engine comprising a slidable piston, a crankshaft having a rotational axis, a connecting rod operatively connecting the crankshaft to the piston; said crankshaft comprising a crank pin and a guide pin rotatable as a unit around the crankshaft rotational axis, each pin having an axis; said connecting rod having a pivotal connection with the piston and a linear slidable connection with said guide pin; and a force transmitting means connecting said crank pin to said connecting rod; said connecting rod having a first force direction line extending through said pivotal connection and the guide pin axis; said force transmitting means having a second force direction line extending through the crank pin axis and a force convergence point on the connecting rod force line remote from the piston pivotal connection. 
     
     
       2. The combination of  claim 1 , wherein said crank pin and said guide pin are contiguous, said crank pin and said guide pin being spaced the same radial distance from the crankshaft rotational axis. 
     
     
       3. The combination of  claim 2 , wherein said guide pin leads the crank pin, measured in the direction of crankshaft rotation. 
     
     
       4. The combination of  claim 3 , wherein the lead angle of the guide pin measures approximately thirty degrees. 
     
     
       5. The combination of  claim 1 , wherein said force-transmitting means comprises a link member having a swivel fit on the crank pin and a hinged connection with the connecting rod. 
     
     
       6. The combination of  claim 1 , wherein said force-transmitting means comprises an arcuate track centered on said force-convergence point; said arcuate track being movable on said crank pin. 
     
     
       7. The combination of  claim 1 , wherein said crank pin and said guide pin are contiguous, said crank pin and said guide pin being spaced a common radial distance from the crank shaft rotational axis; said guide pin leading the crank pin by approximately thirty degrees measured in the direction of crankshaft rotation; said force-transmitting means comprising a link member having a swivel fit on the crank pin and a hinged connection with the connecting rod. 
     
     
       8. A four cycle engine comprising a combustion cylinder, a gas-powered piston slidable back and forth in said cylinder; a crankshaft having a circular crank pin and a circular guide pin movable as a unit around a crankshaft rotational axis; a connecting rod operatively connecting said piston to said crankshaft; said connecting rod having first and second ends, said connecting rod having a pivotal connection to said piston at said first end, and a linear trackway movable on said guide pin, whereby the guide pin and aforementioned pivotal connection jointly determine the orientation of the connecting rod relative to the piston; and a force-transmitting means connecting said crank pin to said connecting rod; said connecting rod having a first force direction line coincident with said linear trackway; said force-transmitting means having a second force direction line that extends through the crank pin axis and a force-convergence point proximate to the second end of the connecting rod. 
     
     
       9. The combination of  claim 8 , wherein said crank pin and said guide pin are spaced a common radial distance from the crankshaft rotational axis. 
     
     
       10. The combination of  claim 9 , wherein the guide pin leads the crank pin, measured angularly around the crankshaft rotational axis. 
     
     
       11. The combination of  claim 10 , wherein the lead angle of the guide pin measures approximately thirty degrees. 
     
     
       12. The combination of  claim 9 , wherein said force-transmitting means comprises a link member having a swivel fit on the crank pin and a hinged connection with the connecting rod; said hinged connection having a hinge axis coincident with the aforementioned force-convergence point on the connecting rod force line. 
     
     
       13. The combination of  claim 9  wherein said force-transmitting means comprises an arcuate track centered on said force-convergence point; said arcuate track being movable on said crank pin.